Alexandra Svokos was six years old, growing up in Franklin Lakes, New Jersey, when she became a Hillary Clinton fan. It was 1998, and Clinton had published Dear Socks, Dear Buddy, a collection of children's letters addressed to the first family's pets. Svokos became so obsessed with the book, she recalls, that she wrote her own letter—not to Socks the cat or Buddy the Labrador, but to Clinton herself. When she got a reply on official White House stationery with the first lady's signature, Svokos was thrilled. Clinton was an early feminist icon for many women of Svokos's generation—long before...